Drier for granular material



Dec. 1, 1953 5, HESS 2,660,810

DRIER FOR GRANULAR MATERIAL Filed March 27. 1951 5 Sheets-Sheet l jz/lii, F15- 1 E k/jo Dec; 1, 1953 B. M. HESS 2,660,810

DRIER FOR GRANULAR MATERIAL Filed March 27, 1951 5 Sheets-Sheet 2 H49 jfi- Ill/II w 5 6'4 6 fiz (/e 7z-(07"$ 37" Ce fi/Yess 1 7 a; r I

Dec. 1, 1953 B. M. HESS 2,660,810

' DRIER FOR GRANULAR MATERIAL Filed March 27, 1951 5 Sheets-Sheet 5 5 Sheets-Sheet 4 JL l k i L B. M. HESS DRIER FOR GRANULAR MATERIAL Dec. 1, 1953 Filed March 27. 1951 P Q L 3- M. HESS DRIER FOR GRANULAR MATERIAL.

Dec. 1, 1953 5 Sheets-Sheet 5 Filed March 27. 1951 FIE- E1 Patented Dec. 1, 1953 TED DRIER FOBJGRANUEAR' MATERIAL Bryce-M.- Hess .Chicagmlll.

'ApplicationMarcli 27; 1951; SerialNo. 217;167

,- 11 Claims.

:11 :This invention; relates to :a batch :type drier for grain or other'granular material andsinrparticwular. it :relates to a drierin iwhi'chthe-"drying r chamber is'so constructed that: there ispracticoal-1y no portion of the chamber which is noti-subjeoted. to the efiect of hot gases.

A i satisfactory grain 1 drier must 'rbe so .1 convv: struoted aas to ipass heated "-air ore-other drying -:-zgas:-through -:a drying :chamber filled: with grain a-in such away that the air intimately contacts substantially-all the grain in 'the' chamber. This "poses :no problem :in a commercial grai-n 'drier, as a grain elevator can dry in a continuous opera'tion so. that all'g'rainpasses successively'through 1 the various parts-of: adrier, and then" to a cooler. Ihe average farm, however, has relatively-little grain, and mustusea batch type drier so that uneven distribution of-hot-air through the chem- -leer-leaves Wet spots in the-grain; and-to conserve space and: reduce equipment-requirements -''itis desirable-to cool the grain inthe-=drier.

Grain driers have commonly-beemmadewith a 'drying ohamber hav-ing alternate tiers-'of-inlet duotsand outlet ducts extending from front to rear' of the chamber. "All the iducts haveopen "bottoms" and" the inlet-ducts are in communica- *tion witha heating' cha-mber. -A1b1ow,er is pro- "vided-to force hot-air and combustion gases .from "the heatin chamber to the inlet ducts. The air "flows out the-bottom of the ,inlet. ducts, through the grain in' the body ofthe ,chamber ,anduinto "the open bottoms 'ofthezoutletducts in the adia- -cent tiers. The "outlet ducts are, openmtolihe --atmosphere at'the rear of ,thendryingiohamber. "Eachduct'has a peaked top, sojthat grainwillbe "distributed more. or' less uniformlyv aroundit.

"If an inlet duct is placedclose tonthe-fitopnof the :chamber, inefficient heat utilization, results because .the quantity of .hotuair .zde'liveredu byithe -'duct .is greatenthah that requiredstomdry the ;small amount of grain abovecthehduct. Thus, customarily theitop. tier,,oiirlucts are outlet :ducts, and these, are located a shortidistancebelqw .the "top of the chamber. gEvenithe outletrduotsccannot be too close to the .topcof the chamber,-b,ecause ;as' .the graindriesit shrinks somewhat. Likewise,

" the angle, of reposeof dry. grainis-lessthanthat of moist grain; so that theconical: piles. 70f; grain (curse-17 iLSitBGZWQYHS. FA-sliding gatemcoyerg the .topenings.

Thomas a battle. extending; beneath. each openin rrwhich;adistributessgrain fromrthenopenmgvmore or less uniformly over the adjacentiwareaeofithe idrier-vchamber. .Ilhe :bafile iselocatedzsufficiently close to the:.openinguthatfiihere iswnot room for 'rmuoh grain .aboveizthe. baflle. .A' .tier1=.of':hot= -gas outlet-ducts is "DOSit'iOHGdeabOVt-E iithe'l iinitial 'ztop level of theigrain irrthetdrying chamberzthat :is, :e-above thez line: .to awhichirthe :zdrying chamber is "filled beforeidrymgrofa batch: of 'rgrain isrcom- =;:menced, with the attendant shrinkage. and-s1umpmg of theegrain :which -iowera-the :top level of 13the= grain .as sdrying: prog-resses so: that somerof ifthe hot gasvfrom the top tier of---'inlet ducts-will -.:pass out the top-of the-grain and thus subject rtheeentirei topwpart of the: body oi -grain to -the Aa'ction ofthe heated'gases.

'Ati thewbottom ofi the chamber is positioned a vsliding dump gate 'zwhioh is locatedabove the ::-:conical hopper bottom. -Lhe bottom :tier of hot saircdischarge zductsvis positioned with the 'lower portions iof theducts in--contact with the/sliding \idump :gatesand these ducts' have side --louvers so iizhat hot air-may pass through the chanriberand enter" the ducts through the louvers, thus contacting ithe grain at the extreme bottom of the :'-dryingchamber. ""Io reduceinventories andsimeplify =manufaoturing-'the top -=outlet duots and 40 grain inlet gate are identical to' the bottom-out- :zlettduots: and' grain dump gate; but for omission i of the louvers from the firstnamed-"ducts.

The ur-nace,- or -air heater is of --the *foroed adraft type uSing*g2.S,*0ll"O1"* butane, -and-- the-hot .za-imand combustion gases are blown through the '2drying -chambembya'centrifugal blower. *Separate controls-are provided so that the blower :-may-'-be operated after the=-furnace is shutdown in order to-cool the dried grain in the :drying schamber.

'Phe invention is illustrated in a preferred form aand an alternative embodiment in the accornmanying drawings in which -Fig' 1 is a side elevation of a preferred embodiment of -the invention :with parts of the side wall-broken awayito show .''the interior -construotion; Fig. 2 is a'front eleva- 1 tion thereof; Riggs-is -a fragmentary view like partly broken away -to-show-inter nal' con- .s stru'ctionof the gra-in= inlet -means; Eig. 4-"isa iragmentary: side'elevation;-partly brolgen away to show other detai1s-of the grain *inleemeans "Eig. isa fragmentary view similar to Fig. 3 but on a larger scale to show the feeding means more clearly; Fig. 6 is a fragmentary end elevation partly in section showing the bottom tiers of outlet ducts with the grain dump gate in closed position; Fig. 7 is a view similar to Fig. 6 but showing the grain dump gate in open position; Fig. 8 is a sectional view of a drier provided with a modified grain feeding element; Fig. 9 is a fragmentary center sectional view of the grain feeding element of Fig. 8; and Fig. 10 is a section taken as indicated along the line Ifl-l i] of Fig. 9.

Referring to the drawings in greater detail, and referring especially to the preferred embodiment of Figs. 1 to '7, inclusive, the drier includes a supporting base, indicated generally at H), having legs ii and a top frame l2 formed of angle members. Corner braces I 3 are provided to give additional rigidity to the supporting base.

The drying chamber, indicated generally at [4, is made up of a plurality of tiers of ducts, there being inlet ducts i and outlet ducts 16. Referring especially to Figs. 1 and 6, it will be seen that the bottom tier of ducts I? and the lowermost tier of inlet ducts l5 are substantially alike, except that the bottom ducts I! have louvered openings 18 in their sides, while the ducts l5 do not.

Each of the ducts l5, I6 and IT is formed from a single piece of sheet metal which is of the proper length to extend from front to rear of the drying chamber. The metal sheet is formed so that each duct has a pair of top panels 2! which come to a peak at their juncture, and a pair of side panels 22 which extend downwardly to the base of the tier of ducts. As seen in Fig. 6, all the ducts are open at the bottom and each tier is provided with end plates 23 which add to the rigidity of the duct, and combine to form the front and rear walls of the drying chamber l4. It will be noted that all the inlet ducts l5 have hot air inlet openings at the right hand end as viewed in Fig. 1 and have solid end plates at the opposite end. Conversely, the outlet ducts l6 have apertures in their end plates 23 at the left hand end to permit air to pass from the ducts it to the atmosphere, and have solid end plates at the opposite end. The open bottoms of the inlet ducts provide shielded openings through which hot gases may diifuse through the grain in the chamber, and the open bottoms of the outlet ducts i6 and the louvered openings of the bottom ducts i! provide shielded openings through which hot gases may enter said ducts.

The end plates 23 have their margins bent at right angles outwardly, as seen in Figs. 6 and 7, so as to provide flanges !9 which extend continuously along the bottom and top margins of each end of each tier of ducts, and flanges 2B which project from the vertical margins of each end plate 23. Thus, it is possible to build up a drying chamber to any desired size by varying the num ber of ducts in each tier and the number of superposed tiers. The ducts may be secured together into tiers, and the tiers of ducts may be secured together as seen in Figs. 6 and 7 by bolts 19a and 20a extending respectively through the aforesaid flanges I9 and 20.

Referring particularly to Fig. 2, it will be noted that the ducts in each alternate tier are offset by A the width of a duct element from the ducts in the immediately adjacent tiers above and below. This, of course, requires that there be half ducts 26. Side plates 27 extend from top to bottom of the drying chamber 14 to close its sides, the side plates 21 being secured to the outer upright flanges 2!! of the outermost end plates 23 in each tier of ducts.

Mounted on top of the drying chamber I4 is a grain feeding element indicated generally at 29, and on top of the grain feeding element 29 is a garner 33 provided with a top 3i and a filler cap 32. The grain feeding element 29 is identical with the bottom tier of outlet ducts [7, except that ducts 33 of the grain feeding element have no louvers, and because of its position in the tiers the element 29 has half ducts 330. at its ends. The element 29 has front and rear plates 34 having bottom flanges 3511. by means of which it may be supported on the uppermost flange l9 of the drying chamber, and a top flange 35b to receive a bottom flange 36 on the material hopper 31}. The three parts may thus be secured together in any suitable fashion along the aforesaid flanges.

As best seen in Figs. 3 to 5 one side wall of the feeding element :29 is slotted at 31 to receive a gate means, indicated generally at 38. The gate means consists of a web formed from a pair of angle members forming end rails 3811. which extend transversely of the ducts 33; and a plurality of angle members 38b forming ribs upon each of which is supported a plate 380. The plates 38c occupy the spaces between the outlet ducts 33, and are substantially flush with the bottom margins of said ducts; and the gate 38 has an opening 38d beneath each duct 33. Brackets 39 are secured to the front and rear plates 34 of the feeding element 29, and rollers 40 on said brackets support the gate 38 for rolling movement transversely of the ducts 33. At the outer ends of the end rails 38a, and secured to both of them, is an angle member 4| to which is secured a bifurcated bracket 42. A feed gate operating arm 43 is pivoted at 44 to a bifurcated bracket 45 fastened to an angle member 46 on the wall of the grain garner 3B. The arm 43 has a slot 41 between the two sides of the bifurcated bracket 42 to receive an actuating bolt 48 by means of which it is pivotally and slidably secured to said bifurcated bracket 42. The lower end of the arm 43 extends close enough to the ground that it may be readily reached by the individual operating the drier, and when the lower end of the arm 43 is moved away from the adjacent wall of the drier the gate 38 moves transversely with respect to the ducts 33 so that the plates 380 are positioned beneath said ducts and the openings 3851 are in register with the spaces between the ducts to permit material to pass from the garner '30 into the drying chamber 34.

The top tier of outlet ducts [6, being offset by one-half the width of a duct element from the outlet ducts 33 of the material feeding element are positioned directly beneath the slots so that their peaked tops serve as baffles to distribute grain entering through the openings and the gate slots 38d more or less uniformly over the breadth of the drying chamber I4.

As is clearly apparent from Fig. 5, the peaks of the top outlet ducts l6 are close enough to the grain inlet gate 38 that no substantial amount of grain remains above said top outlet ducts; and the provision of the outlet ducts 33 in the material feeding element 29 assures that some of the hot air from the top tier of inlet ducts I 5 will pass out the top of the grain in the drying chamber and thus dry all of it.

As best seen in Figs. 6 and 7 at the bottom of the drying chamber I4 is provided a dump gate 49 which is positioned against the lower portions of the bottom outlet ducts I1. The dump gate zeeoaero 4a is constructed. like the: inlet gate 3i. Thus; it; is as plate providedi withe apertures 50, andhas at; its. outer end; an angle: member: 5:]; to which. is. secured; a; bifurcated bracket 52;; and connectedto; the bracket. 52 by means of I a-pinia extending through a slot: 51:- is: a; dump gate one eratingi'arm 55, said arm being. pivotaily con: nectent at 56 to a: bracketd-I fastened to: a wall 21. ofv the drying; chamber UL. The." dump gate 49' operates exactly like the: inlet gate 3.8;. and whom it istopen grain in the: drying chamber. H may pass: into! a. discharge: hopper. 5&- which: is largaenough-toholdall; the grain from. the dry; ing chamber so that the drying; chamber lllma'y lee-refilled; for. a new operation; The dried grain may: be. discharged. from the: hopper. 5.8.- through the hopper mouth 58a: for transportation to: stor age. while the; next batch. ft grain. is being: dried.

Hot air for; the. drying chamber? H. is' provided by: means; of. a heating, system,. indioate'dagenerah ly -at 59. Theheating' system includes-a furnace chamber- 69- proyidedi witha high .efliciency heating-unit 64 which it oil is; to-be used, is of the conventional forced.draft".tagcev As: is well known in. the. art, propane or natural gasmay be used as. fuel by substituting. burner racks for; the forced draft. unit.

Communicating. withthe: furnace chamber 60 is a hot air supply conduit 62 which has aeeentrifngalzblowen 63- at its. lower. end. The blower may be driven. in any conventional manner,. as bya motor 54 operatingthrough sheaves'fifiland 6.6. andabelt. 61.. TheconduitBZ flares from; the month of. the blower. 63 so that at itsouter end it. occupies. the entire. front. wall. of the drying chamber I4, and extends: vertically. a sufficient distance to; include in; its discharge. opening all of theinlet. ducts. 1-5.v

The. furnace. heating unit. fat is started; and stopped. by. means.- of. a furnace switch 6.8 which may. conveniently: bemounted as shown on the inside face. of. one. of: the. braces L3. where it is protected from the weather, and is closeto-the grain inlet. and. dump. gate controL handles: 43 and. 5.5. The. switch is connected. to. the. fan and ignit'er for the heating unit. by means of wires 69, A blower. switch. 10. is connected by wires H to the. blower 63 so-as.to.contro1.operation-of thebl'ower. 'I'hispermitsthe. unit to be operated first with both. the. heating unit. 6L and blower E3. in. operation .to. drythe grain, andl'aten with the heating unit. shut-01fandthe blower operating. to coolthegrain; so. that the single unit-pom forms. both. drying. and. cooling. functions;

The operation. of the. device. believed. to. be

clear from the foregoing description. The dryingohamber: Memay be filled with grain or other granular material from the material garner 30 by manipulating the feed gate operating arm 43 to; move the. gate? member" 38 which covers the feeding openings between theducts 33. The capacity ofthematerial garner '30- is at least equal to that of the drying chamber It. The gate member 3.8: is closed, and. the. furnacea heating unit (it and blower 63 are then, placedainioperation by means of the switches 68.- and T otrespective1y,-; and. heated air and combustion; gases; are blown; through the conduit 62. and: iIltOfi'thE: ducts [5.- The. hot gases pass out the-open bottoms-of theducts. li and diffuse through the grainimt he drying chamber in order. to enter-r the openfbottoms of the outlet ducts l6. Some of the hot gases from the bottom inletcduct-t l are forced downwardly and escape. through the louver'ed openings. l.8 into the bottom outlet ductss IJL and. v

thencethrough the-opemendsof said; ducts to the atmosphere. A-portionof; thezhot-gaseszfionnthe top inlet ducts;- l=.5zpasses=upwardly' through the top of the grainandiescapes through the outlet; ducts 33.. The: time-of operation of the drier-isconztrolled in a manner whichiiswell. known. to the art in. order: to determine the final approximate moisture content of. the: grain. When: the"- de sired: moisture: content. has. beem reached, the switch 6.8. is moved. to off position; and the blower 63 may continue to operate to. blow: unheated air through the conduit 62 to! coat the grain. When asuitable temperature has; been reached;thergrainzmay'be:removed from the dry"- ingi chamber.- by: manipulation. of the operating arm: 55 toropen thedump gate: 49.

The modified: form of drier shown in. Eigsz. 8' to 10, inclusive; is identical with the preferred form except for: the: arrangement. of the feeding: element, which is indicated generally at 1-291. The? modified grain; feedingv element: l29 has top and b'ottomrfiangeslike those of'the'preferred f'ocm; by; means of! whichit is supportedzionn top at the drying: chamber 44-- and. in: turn supports the gamer 3.0.

The grain feedingselement: I29 has; three rows of: material: feeding; outlets- I317, each of which rows? extends from. side to side of the drying,

chamber-and: has a pair-of flanking; angularly" dis.- pose'd material feeding plates; I318 to' divide: the flow of. material. andadirect it: to .the: openings; 1:31 A. movablegate member 1233: positioned over each ofthe rows: of feeding: openings. 137;. the gate members I139 beingzprovided with: apertures which may be moved into or out of alignment with the: apertures. l3slso as. t0? control: the flow of. grain: from the garner 3i!- drying chamber Mr. Asseen: in Fig-i. 1'0, thergate members l-3&; haverthein endipontions extending through slots in atsidewall l dfl ofzthe feeding section; 129;, and: are bolted. to: an. actuating: bar Ht! which extends-.acrossetheends'of' of said gate-members.- l'39.. The. feeders gate: operating mechanism. isJike? thator the prefernedformgand need; not. be: described: detail. It: includes an operating arrm I 43:; which; may-have lower end moved; away; from: the wall of"- the: drier: to move ailthree gate: members; 1 39 so; as: to? bring the apertures-in: them: into negistenwith' the material feeding: openings I31: and permit materiai; to

'flowfronr-the garner. 30. into-the drying Ohm ber It.

Positioned; within. the: material: feeding: section 219;. immediately beneath; each: row ofi' feeding openings 31* ist a. plate: which is: longitudinally bent atright-angles' to form a baffle having slanting faces extending; continuously beneath each1of: the: feeding; openings I391? so that the baffles M?! tend to distribute: material; from. the feeding; openings generally. uniformly oyer the area of. the. drying: chambee M. Eikewise, the baffles occupy. space: below the .materiali inlet openings. which woulcLbe fillediwith heaps-of. ma terial were it not for the presence of the battles. Thus; the bafiles reduce? the quantity 'of material ins the tonpart. of the drying chamber. [4,. and thus. reducev the amountv of: material} whicln is not reached by. anadequate quantity of hotzain'duning the drying operation.

In. order. to permit some'hotair to passzthrough the. grainwhich. lies: in the top part; of. the drying chamber IL during.v a.- drying operation; an outlet; opening. I 48-c is. pnonidedv in: eaohaof the: side plates MB. of. thegrainofeedingsection- 129 immediately beneatheach. ba-flie I431. Thus-,. the

7 combination of the baffles I41 with theapertures I48 serves substantially the. same function in the modified form as is served in the preferred form by the tops of the top tier of outlet ducts l and by the auxiliary outlet ducts 33 in the grain inlet section 29.

The foregoing detailed description is given for clearness of understanding only and no unnecessary limitations should be understood therefrom, as modifications will be obvious to those skilled in the art.

I claim:

1. A drier for granular material comprising, a drying chamber, feeding means at the top of said chamber, a plurality of spaced imperforate, open bottom inlet ducts for introducing hot gases to said chamber, a plurality of imperforate, open bottom outlet ducts interspersed among said inlet ducts and spaced therefrom, said outlet ducts "having open ends through which said gases may leave the chamber, and all said ducts having tops constructed to distribute grain more or less uniformly to both sides of the duct, a lowermost series of outlet ducts having imperforate tops and shielded side openings through which hot gases may enter said ducts, and open ends through which hot gases may leave said ducts, dump gate means substantially in contact with the lower margins of said lowermost series of ducts and close to the shielded side openings therein, a heating chamber in communication with said inlet ducts only, said chamber having heating means, and'a blower to circulate hot gases from said heating chamber through the drying chamber.

2. The drier of claim 1 in which the lowermost ducts are spaced apart by distances substantially equal to their width and the dump gate means comprises a slidable plate in contact with the lower margins of said ducts and having openings tioned close beneath each feeding opening, and

auxiliary hot gas outlet means is positioned immediately above the initial top level to which the chamber is filled with grain before drying begins. '4. The drier of claim 3 in which the feeding openings are parrallel slots extending substantially from wall to wall of the drying chamber parallel to the gas ducts, and the bafiles are formed by the tops of a tier of outlet ducts extending continuously beneath the openings. .5. The drier of claim 4 in which the auxiliary hot gas outlet means comprises an open bottomed outlet duct positioned between each pair of slots with its base generally flush with said slots.

iii)

' 6. The drier of claim 3 in which the bafiies are tom hot gas inlet ducts and hot gas outlet ducts in said chamber respectively to admit gas to and release gas from the chamber, the lowermost tier of inlet ducts being spaced above the bottom of the drying chamber and the uppermost tier of inlet ducts being spaced a sufficient distance below the initial top level to which the chamber is filled with grain before drying begins that the open bottoms of said uppermost tier of inlet ducts are below the top level'of grain at the completion of a drying operation, a lowermost series of outlet ducts having imperforate tops and shielded side openings through which hot gases may enter said ducts and open ends through which hot gases may leave said ducts, said lowermost series of outlet ducts being at the bottom of the drying chamber, inverted V'-shaped baffie means extending continuously beneath each of said feeding openings to distribute grain from the opening, auxiliary hot gas outlet means above the initial top level to which the chamber is filled with grain before drying begins, a heating chamber in communication with said inlet ducts only, a blower to circulate hot gases from said heating chamber through said drying chamber, and horizontally movable dump gate means at the bottom of the drying chamber in contact with the lower margins of said lowermost series of outlet ducts.

8. The drier of claim 7 in which the baffle means is formed by the top of the uppermost tier of outlet ducts, and the auxiliary hot gas outlet meansis formed by an auxiliary tier of open bottom ducts equal in width to said feeding open ings which have their bottoms in contact with said feeding gate means.

9. The drier of claim '7 in which the horizontally movable feeding gate means comprises a plate having apertures normally aligned with the bottoms of the auxiliary tier of outlet ducts, and an operating handle by which the gate means may be moved toalign said apertures with said openings.

10. The drier of claim '7 in which the bafile means is positioned above the initial top level of grain in the drying chamber and the auxiliary hot gas outlets are formed by apertures in the outer walls of the drier beneath said bafiles.

11. The drier of claim? in which the lowermost ducts and spaced therefrom, said outlet ducts equal to their widths, and the dump gate means comprises a slidable plate in contact with the lower margins of said ducts and having openings beneath them, and an actuating lever for sliding said plate transversely of the ducts.

BRYCE M. HESS.

References citesm the file of this patent UNITED STATES PATENTS 

